Analytical and Numerical Solutions for Frames with Softening Hinges
Publication: Journal of Engineering Mechanics
Volume 123, Issue 1
Abstract
The paper describes beam elements with inelastic hinges capable of modeling softening due to damage in building frames under severe loadings. A condition for uniqueness on the element level is derived, and the behavior of the model is compared to analytical solutions of simple structures (a single column and a portal frame). An application to postpeak analysis of a multibay frame is presented. Depending on the beam-to-column stiffness ratio and on a certain ductility parameter, various failure modes can occur, ranging from distributed to highly localized ones. This leads to a special type of size effect on the peak load, which is assessed numerically and related to analytically derived solutions valid in extreme situations—the elastic limit and the plastic limit.
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Published In
Journal of Engineering Mechanics
Volume 123 • Issue 1 • January 1997
Pages: 8 - 14
Copyright
Copyright © 1997 American Society of Civil Engineers.
History
Published online: Jan 1, 1997
Published in print: Jan 1997
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